Assessment of the esthetic smile in young Japanese women

Statistics Standard errors of the measurements were calculated. Independent student's t -tests were used to compare statistically the measurements of Group 1 patients and Group 2 model samples, and also those of BCS and the widths of the upper dental arch (UAW). Mean and standard deviation were calculated and p < 0.05 was significant. Results and conclusion The average smile, smile curve arch line without touching the lower lip, parallelism of the upper incisal curve with the inner curvature of the lower lip, no display of the 1st molar, 1:1 ratio of the widths of nose and upper cuspid, a minimum buccal corridor with no significant relation in widths of the upper dental arch all corresponded to ideal smile. Keywords Buccal corridor Smile arch Smile index Upper arch width